Your done- /tmp is now mounted as noexec. You can sleep a little bit safer tonight. I created a hello world c++ and compiled it then moved it to /tmp. Upon trying to run it (even chmod +x’ed), it gives the following error:

bash:./a.out:Permission denied

good luck! if it is causing problems with any of your software, you could remove the entry from fstab, reboot and then delete /tmp and recreate it to bring it back to normal.